The present invention relates generally to sea walls, and more specifically, to a method and system for repairing sea walls and preventing erosion drainage from occurring on the landward side of the sea wall.
Many areas adjacent to naturally-occurring and man-made bodies of water are bordered by sea walls. Sea walls, when adequately designed and constructed, serve to protect waterfront property and improvements located thereon against wave attack and serve to stabilize the shoreline. Even with appropriate design and construction features, sea walls have been known to fail and fall into bodies of water because of the passage of time, strong winds, heavy rains, erosion, corrosion, high and low tides and other reasons. Therefore, sea walls must be protected against the action of the elements not only in front of the wall, but also behind it. Posterior wall protection is particularly necessary to counter erosion of soil, caused by hydrostatic pressure buildup which can result from waves lapping over the top of the wall and from ground water and rain percolating through the soil and toward the wall.
A typical sea wall will be constructed of a number of stone or concrete slabs which are square or rectangular in form and which are positioned side-by-side along a shore line to form a continuous wall. In such formation, each of the slabs frequently will be vertically implanted along one of its sides into the bottom of the body of water and close to the water""s edge. Slab implantation will usually be performed so that a gap is left between adjacent slabs. The primary purpose for leaving such a gap is to provide space for expansion and contraction of the slab elements as water, land and air temperatures vary daily and seasonally. Additional construction features of the slab-type sea wall include providing each wall element with an anchor system, a number of drainage holes and filter material. The anchor system, which typically extends from the wall element to the earthen embankment behind the wall element, serves to keep the element in its vertical orientation and in firm contact with the embankment. The drainage holes, or xe2x80x9cweep holesxe2x80x9d as they are sometimes called, are provided through the upper region of the wall element at horizontal intervals and function to permit drainage of water from within the embankment to the side of the wall facing the body of water. The filter material, which is sheet-like in appearance, is flatly laid along the entire length of the sea wall between the posterior surface of the wall and the embankment and is provided to resist erosion of embankment material as water flows from the embankment through the weep holes and the wall element gaps.
While the filter material can be expected to function satisfactorily for a period of time after the sea wall has been constructed, eventually the filter material adjacent to the weep holes and the gaps deteriorates and sink holes then can develop in the embankment behind the sea wall. If such sink holes are allowed to grow unchecked, one or more portions of the sea wall may fall into the body of water as the anchor system loses its footing in the embankment. Until the present time, the procedure available for averting such a sea wall failure involved excavation of the embankment to expose the deteriorated filter material, removal of that material, reinstallation of new filter material and replacement of the embankment. Such procedure has been found to be not only time-consuming, but also very costly, since more often than not, it is necessary to use heavy excavating machinery to carry out the process.
The present invention provides a novel process and system that may be employed to more quickly and easily repair a sea wall and halt erosion drainage damage at considerably lower costs than those encountered through practice of the previously available technique.
In accordance with a preferred embodiment of the invention, a new and useful system and process are provided for precluding erosion drainage from occurring on the landward side of a sea wall when a filter material provided at a plurality of weep holes in the wall and at expansion and contraction gaps between wall elements degenerates. The system of the present invention generally is comprised of: a pipe-like conduit, open at both of its ends and having an outside diameter that is substantially the same as, or slightly larger than, that of the weep holes; a removable cap-like protector means that is insertable over either of the ends of said conduit and used for a purpose as hereinafter set forth; a filter assembly comprising a sleeve-like enclosure having an outside diameter that is slightly smaller than the inside diameter of said conduit and having a first inside bore and a second inside bore, with the first inside bore being smaller in diameter than the second inside bore and a filter situated within said filter assembly or sleeve-like enclosure; and an a rod-like implement insertable within said pipe-like conduit and engageable with said sleeve-like enclosure. The process of the present invention generally comprises the steps of: reaming each of the weep holes with a drill so as to clear each of the holes of any accumulation of debris; scraping each of the gaps between the sea wall segments and an area of the sea wall extending to the left and right of each of the gaps so as to remove any barnacles or other foreign objects which may have become adhered to the gaps and the nearby sea wall surface; sealing each of the gaps with a hydraulic cement; installing one of the pipe-like conduits in each of the previously reamed weep holes by inserting one end of the pipe-like conduit into the opening of the weep hole and by applying the cap-like protector over the other end of the pipe-like conduit and then striking the cap-like protector with a hammer or any other suitable impact producing device to drive the pipe-like conduit into the weep hole; thereafter removing the cap-like protector from the pipe-like conduit; releasably fastening the sleeve-like enclosure containing the filter to the rod-like implement; inserting the rod-like implement and the sleeve-like enclosure into the pipe-like conduit and sliding the sleeve-like enclosure along the inside of the pipe-like conduit until it is positioned at the landward side of the sea wall; unfastening the rod-like implement from the sleeve-like enclosure; and withdrawing the rod-like implement from the pipe-like conduit.
In instances where, after the initial installation of the system of the present invention in accordance with above enumerated steps, the filter means contained in said sleeve-like enclosure attains a deteriorated, non-functional state, the process of the present invention will then further include the steps of: reinserting the rod-like tool into the pipe-like conduit; releasably fastening the rod-like tool to the sleeve-like enclosure containing the spent filter means; slidably withdrawing the rod-like tool and the sleeve-like enclosure from the pipe-like conduit; removing the spent filter means from the sleeve-like enclosure and inserting a new filter means therein; reinserting the sleeve-like enclosure containing the new filter means into the pipe-like conduit; unfastening the rod-like tool from the sleeve-like enclosure; and withdrawing the rod-like tool from the pipe-like conduit.
Unlike the previously available method for remedying erosion drainage, which has to be carried out on the landside of the sea wall, the process of the present invention can be implemented wholly from the side of the sea wall facing the body of water. This aspect of the present invention thus eliminates the need to excavate the embankment on the landside of the sea wall and does away with the prospects for having to use costly excavating equipment. Additionally, because the inventive process entails use of hydraulic cement which may be applied in the presence of water and the pipe-like conduit of the inventive system may be inserted into a weep hole opening regardless of its location, the present invention permits drainage erosion control work to be undertaken right in the body of water itself and without having to first pump water away from the front surface of the sea wall. The ability to perform the work in the water makes it possible to halt drainage erosion in a fraction of the time required to do so with the previously known process. Thus, it is an object of the present invention to provide a low cost system and process that precludes erosion drainage from occurring at gaps and at weep holes in a sea wall by eliminating the need to excavate an earthen embankment on the landside of the sea wall in order to expose and replace deteriorated filter material thereat.
It is a further object of the present invention to provide a highly efficient system and process that precludes erosion drainage from occurring at gaps and at weep holes in a sea wall by permitting remedial efforts to be carried out wholly from the side of a sea wall that faces a body of water and within the body of water itself.
These objects and others of the invention will become apparent in the following detailed description of the invention when considered in conjunction with the accompanying drawings.